A larger capacity battery will last longer.
We do not offer them for sale on our website, but you can purchase compatible batteries at a local hobby store, or online.
They are physically larger and won’t fit perfectly into the battery compartment but they will work with the machine. Here are just a few examples:
You just want to be sure you're getting an 11.1v battery that has an xt60 connector and does not have a discharge rate of over 60c. Here are some examples of: